OBJECTIVES: Donepezil is the most prescribed medication to treat symptoms for patients with Alzheimer’s disease (AD). In 2021, aducanumab was approved by FDA for early AD, however, with a high price and controversial effectiveness. This study aims to assess the cost-effectiveness of aducanumab versus donepezil for patients with early AD.

METHODS: A five-state Markov model was constructed, with a lifetime time horizon and a one-year cycle time. Transition probabilities and mortality rates were obtained from literature reviews. The perspective of the study was from the U.S. healthcare system, and direct medical costs were included. The unit price of aducanumab was US$479.40 for a 170 mg vial and US$846.00 for a 300 mg vial. Inpatient and outpatient costs for patients with AD were obtained using real-world claims data. Utilities were obtained from literature. The discounting rate was 3%. Incremental analysis was used in the base case analysis to assess the cost-effectiveness. One-way and probabilistic sensitivity analyses were performed for uncertainty and generalization of the base case result.

RESULTS: From the perspective of the U.S. healthcare system, the ICER of patients using aducanumab compared to those using donepezil was US$2,558,707.3 per QALY gained, which was much greater than the WTP threshold of US$50,000 to US$150,000, indicating that using aducanumab was not cost-effective. One-way sensitivity analysis showed the most sensitive parameter was the relative risk (RR) of progressing from MCI to mild AD of aducanumab. In the probabilistic sensitivity analysis, when the willingness to pay was the WTP threshold of US$150,000, the probability of aducanumab being cost-effective was 0%. In addition, when the probability of aducanumab being cost-effective was 50%, the WTP was US$1,560,000.

CONCLUSIONS: Compared to donepezil, aducanumab generates marginally incremental effectiveness with a considerable incremental cost, indicating that it is not cost-effective from the perspective of the U.S. healthcare system.